Background: The relationship between patient adherence and treatment outcomes has been documented across chronic health conditions, but the evidence base for effective adherence interventions in human immunodeficiency virus (HIV) and acquired immune deficiency syndrome (AIDS) requires more rigorous research and reporting.
Objectives: The aims of this study were to determine whether a tailored, nurse-delivered adherence intervention program-Client Adherence Profiling and Intervention Tailoring (CAP-IT)-improved adherence to HIV medications, compared with standard care, and to identify the relationship among adherence measures.
Methods: A randomized controlled trial (RCT) with repeated measures was used to test the efficacy of CAP-IT over a 6-month period. A convenience sample of 240 participants was recruited from a freestanding public HIV/AIDS clinic in Houston, TX, that provides medical, psychological, and pharmaceutical services for over 5,000 clients. Study instruments and measures included demographics; chart audit to capture CD4 count, viral load, and prescribed medications; health literacy; and five measures of adherence (AIDS Clinical Trial Group-Revised Reasons for Missing Medications, Morisky Self-Report of Medication Non-Adherence, Pill Count, Medication Event Monitoring System [MEMS] caps, and Pharmacy Refill).
Results: A logistic regression using generalized estimating equations method showed no significant differences over time on the five medication-adherence measures between the experimental and control groups. Little correlation was documented among the five different adherence measures, and there was minimal correlation with clinical markers.
Discussion: It is unclear why the tailored adherence intervention was not efficacious in improving medication adherence. The findings suggest that these measures of medication adherence did not perform as expected and that, perhaps, they are not adequate measures of adherence. Effective and efficient adherence interventions are needed to address the barriers to medication adherence in HIV/AIDS.